fieldmarks: Eel-like shark with 6 gill slits, terminal mouth with tricuspid teeth in both jaws, and one dorsal fin.

Body slender and eel-like, with prominent keels on abdomen.
Head with 6 pairs of gill slits, the lower ends of the first gill slits connected to each other across throat;
snout extremely short, truncated; mouth terminal on head, very long;
teeth alike in upper and lower jaws, with three strong cusps and a pair of intermediate cusplets, not saw or bladelike, posterior teeth not minute and granular.
Anal fin large, larger than dorsal fin; caudal fin without a subterminal notch.

Wide-ranging but spottily distributed. Eastern Atlantic: From northern Norway, the Atlantic Slope off northern Scotland and western Ireland, France, Spain, Portugal, Morocco, Mauritania, Madeira, Angola, northern Namibia, and possibly the eastern Cape of Good Hope, South Africa. Western Indian Ocean: Off South Africa. Western Pacific: Off Japan (southeastern Honshu), Australia (New South Wales), and New Zealand. Eastern Pacific. Southern California, USA, northern Chile.

Habitat and Biology

Benthic on the outer continental and insular shelves and upper slopes,at depths usually between 120 and 1280 m, but occasionally taken at the surface.

A rare, little known deepwater shark.Ovoviviparous, number of young 8 to 12. Apparently reproduces all year in deep water off Japan; gestation period probably very long, one to two years.
Feeding habits unknown, but the needle-sharp, slender-cusped teeth of this shark suggest feeding on deepwater cephalopods and bottom fishes.

Size

Maximum 196 cm, size at birth about 39 cm; size at maturity about 97 cm for males and 135 cm for females.

Interest to Fisheries

Of little importance, taken incidentally in bottom trawls catches, formerly caught with deepset longlines off Japan.Utilized for fishmeal and for human consumption.

Remarks

Threat to humans: Not dangerous, but teeth can lacerate the hands of the unwary scientist examining its mouth.